QiAnXin Threat Intelligence Center's RedDrip team tracked the relevant events and discovered a batch of attack samples exploiting the CVE-2023-23397 vulnerability. After analyzing these samples and C2 servers, we believe that the exploitation of this vulnerability in the wild has been ongoing since March 2022. In the later stages of the attack, the attackers used Ubiquiti-EdgeRouter routers as C2 servers, and the victims of the attack activity were from multiple countries.
Exfiltrated Russian-written documents provide insights into cyber offensive tool projects contracted by Vulkan private firm for the Russian Ministry of Defense.
Scan-AS is a database used to map adversary networks in parallel or prior to cyber operations. Scan-AS is a subsystem of a wider management system used to conduct, manage and capitalize results of cyber operations.
Amezit is an information system aimed at managing the information flow on a limited geographical area. It allows communications interception, analysis and modification, and can create wide information campaigns through social media, email, altered websites or phone networks.
QakBot is a banking trojan that has been evolving since its first version was discovered in 2008. According to the 2022 report published by CISA, it was one of the most active variants in 2021, and during 2022 and so far in 2023 it has remained quite active. Taking a brief look at the latests news of QakBot it has been updating its tactics constantly, for example, using a Windows zero-day to avoid displaying the MoTW or the most recent one, using OneNote files to drop QakBot.
In this case we are particularly interested in the anti-analysis techniques used by QakBot during the early stages of its execution. These techniques can make malware analysis harder if they are not known, so learning to identify and bypass them is essential to get to see the malware’s operation at its full potential. Furthermore, there are techniques that can replicate / adopt different types of malware, so knowking them opens the door to the study of different samples.
On 02 February 2023, an alert triggered in a Huntress-protected environment. At first glance, the alert itself was fairly generic - a combination of certutil using the urlcache flag to retrieve a remote resource and follow-on scheduled task creation - but further analysis revealed a more interesting set of circumstances. By investigating the event in question and pursuing root cause analysis (RCA), Huntress was able to link this intrusion to a recently-announced vulnerability as well as to a long-running post-exploitation framework linked to prominent ransomware groups.
Sliver is an open-source penetration testing tool developed in the Go programming language. Cobalt Strike and Metasploit are major examples of penetration testing tools used by many threat actors, and various attack cases involving these tools have been covered here on the ASEC blog. Recently, there have been cases of threat actors using Sliver in addition to Cobalt Strike and Metasploit.
The ASEC (AhnLab Security Emergency response Center) analysis team is monitoring attacks against systems with either unpatched vulnerabilities or misconfigured settings. During this process, we have recently discovered a Sliver backdoor being installed through what is presumed to be vulnerability exploitation on certain software. Not only did threat actors use the Sliver backdoor, but they also used the BYOVD (Bring Your Own Vulnerable Driver) malware to incapacitate security products and install reverse shells.
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IOCs are listed on this page below all of the images.